VFG.Kml=function(){
}
VFG.Kml.Primitives=new Map();
VFG.Kml.add=function(viewer,options){
	let _this=this;
	if(!this.Primitives.has(options.id)){
	    viewer.dataSources.add(Cesium.KmlDataSource.load(options.url, {
	        camera : viewer.scene.camera,
	        canvas : viewer.scene.canvas,
	        clampToGround:options.clampToGround?options.clampToGround: true //开启贴地
	    })).then(function(dataSource){
	    	console.log(dataSource);
	    });
	}else{
	}
}


